The objective of this proposal is to continue engineering development and pre-clinical testing of a novel percutaneous mechanical circulatory support (pMCS) device for use during high risk percutaneous coronary intervention (PCI) and cardiogenic shock (CS). The high-incidence of PCI and CS are significant and increasing worldwide, representing a major burden in terms of health care resources and costs. Current treatment options, including medications and other medical devices, are limited by ineffectiveness, insufficient support, adverse events, and/or require major surgical intervention. To address this need, RT Cardiac Systems (RTCS, Cary NC) has developed novel blood pump technology enabling greater hemodynamic support than previously possible. Other companies report high ?peak flows? at sub-therapeutic aortic pressures indicative of poor patient prognosis and/or severe aortic insufficiency. The RTCS device provides mean flow over 4 L/min against mean aortic pressure of 80 mmHg, which is sufficient to restore end organ perfusion. Other known devices can only produce mean flows of 3 L/min or less at this therapeutic condition. With extensive blood pump design gained developing the HeartWare HVAD, MVAD, and intraventricular MVAD family of chronic LVAD?s, RTCS has achieved this high level of support with low levels of blood trauma. Subsequently, RTCS has the expertise, experience, and confidence that we will achieve our objective of commercializing a competitive pMCS device to improve therapy for high-risk PCI and CS patient populations. The proprietary RT Cardiac System pMCS device (US patent application 15/676,281) consists of a miniaturized axial flow pump (2-bladed impeller, 3-bladed diffuser) and an intravascular motor (slotted, brushless DC motor) connected via a short flexible drive system. The device flexibility improves implantation and resistance to occlusion as the device adapts to the native left ventricle anatomy. The short drive system design, including bearing material selections, does not require an external purge of lubrication system that is required of all other known devices. The high hydraulic efficiency of the pMCS device reduces blood trauma, required motor torque, and rotational speed to achieve design flow rates. The high motor efficiency reduces the power required and heat dissipation load. Rigor of prior research with proof-of-concept testing was demonstrated as evidenced by completion of flow visualization (capacity, washing, blood preservation) and in vitro (hydraulic and electro-mechanical performance) analyses. In this phase I project, we will (1) complete fabrication of the pMCS motor system (Aim 1); (2) demonstrate engineering performance in static (HQ curves) and dynamic (hemodynamics) mock loop model (Aim 1), (3) demonstrate system reliability in 30-day system reliability testing (Aim 1), (4) demonstrate physiologic efficacy (hemodynamics, blood, imaging) in a large animal model (Aim 2), and (5) evaluate surgical placement in a large animal model (Aim 2). Successful demonstration of feasibility of the RTCS pMCS system will include: (1) novel drive system reliability, (2) achieve engineering performance benchmarks, (3) physiologic efficacy (pump flow, minimal hemolysis), and (4) device in vivo delivery and positioning. Collectively, upon successful demonstration of meeting design benchmarks and study metrics (phase I), we will work to achieve a design freeze, complete verification and validation testing in compliance with Good Manufacturing Practices (GMP), and pre-clinical testing in compliance with Good Laboratory Practices (GLP) with all of our engineering control documents and pre-clinical test data and analyses used to support a IDE application for a clinical trial in PCI and CS patients. Our vision is to successfully translate the pMCS system and a family of catheter-based products into clinical practice for high-risk PCI and CS in adults as well right heart and biventricular failure therapies in adult and pediatric patients.